A communication network on which information is transmitted and received among the plurality of locations is necessary to assemble a service with distributed services provided at a plurality of locations (e.g. Tokyo and Osaka). The communication network, however, does not always have a wide enough communication bandwidth. Therefore, a sufficiently wide communication bandwidth on the communication network is not always secured when the service is provided.
In Service-Oriented Architecture (hereinafter, abbreviated as “SOA”), a function corresponding to a process step in an operation is regarded as a service. Moreover, in SOA, the overall system is assembled by making the services coordinated with one another on the communication network.
Extensible Markup Language (hereinafter, abbreviated as “XML”) is a language employed when, for example, a system based on SOA is assembled. However, a document described XML (hereinafter referred to as “XML document”) includes formal descriptions such as a tag.
Efficient XML Interchange (hereinafter, abbreviated as “EXI”) is a technology reducing formal descriptions in an XML document. EXI compresses an XML message such as a document described in XML by reducing formal descriptions. In EXI, it takes a lot of calculation to compress the XML message, and, furthermore, file size after compression is not sufficiently small.
In a system based on SOA, the XML document defining the system contains formal descriptions. Furthermore, in a system based on SOA, because schema of the XML document is defined for each service, messages associated with an identical service are similar to one another. In addition, a communication network does not always have a wide enough communication bandwidth. Therefore, in a system based on SOA, it is necessary to use the communication bandwidth efficiently.
A data communication system disclosed in Patent Document 1 (Japanese Patent Application Laid-Open No. 2007-299019) or a communication data reduction method disclosed in Patent Document 2 (Japanese Patent Application Laid-Open No. 2003-308444) reduces communication volume for transmitting and receiving information via a communication network.
The data communication system disclosed in Patent Document 1, when requested data is transmitted, generates differences between the data to be transmitted and all data stored in a cache, and transmits a difference with the smallest size among the generated differences and an identifier identifying the data from which the smallest difference is produced. By the data communication system, communication volume is reduced.
The communication data volume reduction method disclosed in Patent Document 2 is a method in which, when a message for a transaction is transmitted, difference information between a message for any of past transactions and the message for the transaction is generated with conforming to a standard specification for BtoB (business to business) and the generated difference information is transmitted to a transaction partner. By the method, communication data volume in electronic commerce is reduced.
Patent Documents 3 to 7 also disclose technologies related to the present invention.
A communication control apparatus disclosed in Patent Document 3 (Japanese Patent Application Laid-Open No. 2002-123498) forms a group with users identified by user identifiers which are included in user identifiers that identify users belonging to a group and also included in user identifiers associated with users who can be communicated with. The communication control apparatus keeps shared data of a collaborative operation support system, which halts execution temporarily, correct and consistent after the execution is resumed.
An operation support system disclosed in Patent Document 4 (Japanese Patent Application Laid-Open No. 2010-198191) includes an operation history database capable of storing a history of operations carried out by a user in the past, a similar history extraction unit that extracts a history of operations similar to a history of operation carried out by the user most recently from the operation history database, a characteristics quantity calculation unit that calculates characteristics quantity of the extracted history, and a similarity ratio calculation unit that calculates a similarity ratio between characteristics quantity calculated in the past and the characteristics quantity of the extracted history. The operation support system, even if a menu selected by a user does not include information related an intention of the user, estimates the intention of the user in the menu selection phase.
A logging control apparatus disclosed in Patent Document 5 (Japanese Patent Application Laid-Open No. 2010-134705) includes an event recording unit that stores a history of events taking place in a device into history information and, when a malfunction takes place in the device, if it is decided that log information needs to be recorded based on a result of comparison between events which take place after the malfunction and events included in the history information, generates a log on the events. In other words, the logging control apparatus generates a log which can be referred to in malfunction analysis.
An information processing apparatus disclosed in Patent Document 6 (Japanese Patent Application Laid-Open No. 2009-163393) includes an acquisition unit that acquires, from history information on sent electronic mail messages, first history information including, as the destination thereof, a portion of destinations of an electronic mail message commanded to be sent, a calculation unit that calculates a similarity ratio between character data in the electronic mail message commanded to be sent and character data included in the first history information, and a warning unit that issues warning information when the similarity ratio does not satisfy a predetermined condition. In other words, the information processing apparatus decreases wrong transmission by issuing warning information when there is no record of sending an electronic message having a similar subject or text even if there is a record of sending a message to the destination address.
An authentication system disclosed in Patent Document 7 (Japanese Patent Application Laid-Open No. 2009-009541) decides that, when it is decided that specific history information in history information of the authentication apparatus and history information designated by specification information which designates the specific history information in the history information have common information, the terminal is a legitimate terminal. The authentication system carries out authentication between a plurality of users or terminals.